Most medical instrument sterilization containers use some form of security device to give evidence of sterile integrity prior to use. One such device is a shrink band that is placed around a pair of tabs that separate when the container is opened. The band is placed around the pair of tabs loosely, but the band shrinks onto the tabs when the container goes through heat sterilization. It is thereafter necessary to break the band in order to open the container.
Several problems have arisen in the use of these security bands. The bands are conventionally made out of expanded polypropylene, which has a natural inclination to stick to metal when it shrinks. When the band breaks, a broken portion sometimes sticks to one of the tabs in an inaccessible location. Sometimes the band will break in several pieces, also causing an inconvenience.
Release agents coating the band have conventionally been provided in order to prevent the band from sticking onto the tabs. These release agents are in the nature of lubricants, such as oil, silicone or other substances. The release agents can either be applied to coat the outside of the band or can be formulated into the band polypropylene mixture to eventually be sweated out onto the surface of the band.
In addition to increased cost, these release agents cause problems in that the band will be totally released from the container, and may shoot through the air like a rubber band and enter an operating "sterile theater". Since the band is disposed on the outside of the container, it is contaminated, and thus it is hazardous to introduce it in an uncontrolled way into a sterile environment.
In view of the problems with conventional security bands, there exists a need for a security band that has a controlled release and which will adhere to an easily accessible portion of the container so that it can be easily removed.